1. Field of the Invention
The present invention relates to an automatic stop control circuit for a camera.
2. Description of the Prior Art
A camera of a TTL light intensity feedback metering system is known. A camera of this type has an electromagnetic release device which is actuated so as to perform a shutter release operation based upon a switch signal in association with a shutter button. While a stop is being closed, light passed through the stop is measured. When the photo metering output signal is detected to have a predetermined relationship with a preset shutter speed and a preset film sensitivity, a stop latch electromagnetic device is actuated to stop the stop-down operation. A camera of this type adopts the shutter priority automatic exposure system or the programmed exposure control system. In such a camera, as the photographing operation is performed, the electromagnetic release device is actuated. When the pole piece is separated from the magnetic core of the electromagnet constituting the electromagnetic release device, a counter electromotive pulse is generated in a solenoid operated coil to adversely affect the photo metering output signal. Then, before the stop is set at a predetermined stop value, the stop-down stop electromagnetic device is actuated, and the stop is stopped. An erratic operation is particularly frequently caused when the brightness of an object is low and the output current from a photo metering light-receiving element is small. In order to prevent such an erratic operation, the photo metering circuit and the electromagnetic release device are separated from each other and arranged inside the camera. Alternatively, one of the photo metering circuit and the electromagnetic release device is electromagnetically shielded, so that the counter electromagnetic pulse wil not adversely affect the photo metering output signal. However, in a small space inside the camera, such a measure cannot be taken, and an erratic operation is difficult to prevent.